/*
 * Copyright 2002-2015 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.springframework.security.web.authentication.handler;

import org.springframework.security.core.AuthenticationException;
import org.springframework.security.web.authentication.handler.AuthenticationFailureHandler;
import org.springframework.util.Assert;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.LinkedHashMap;
import java.util.Map;

public class DelegatingAuthenticationFailureHandler implements AuthenticationFailureHandler {

    private final LinkedHashMap<Class<? extends AuthenticationException>, AuthenticationFailureHandler> handlers;

    private final AuthenticationFailureHandler defaultHandler;

    public DelegatingAuthenticationFailureHandler(LinkedHashMap<Class<? extends AuthenticationException>, AuthenticationFailureHandler> handlers, AuthenticationFailureHandler defaultHandler) {
        Assert.notEmpty(handlers, "handlers cannot be null or empty");
        Assert.notNull(defaultHandler, "defaultHandler cannot be null");
        this.handlers = handlers;
        this.defaultHandler = defaultHandler;
    }

    @Override
    public void onAuthenticationFailure(HttpServletRequest request, HttpServletResponse response, AuthenticationException exception) throws IOException, ServletException {
        for (Map.Entry<Class<? extends AuthenticationException>, AuthenticationFailureHandler> entry : handlers.entrySet()) {
            Class<? extends AuthenticationException> handlerMappedExceptionClass = entry.getKey();
            if (handlerMappedExceptionClass.isAssignableFrom(exception.getClass())) {
                AuthenticationFailureHandler handler = entry.getValue();
                handler.onAuthenticationFailure(request, response, exception);
                return;
            }
        }
        defaultHandler.onAuthenticationFailure(request, response, exception);
    }
}
